JP5962108B2 - Binder resin composition for non-aqueous secondary battery electrode - Google Patents

Description

  The present invention relates to a binder resin composition for a non-aqueous secondary battery electrode excellent in electrolytic solution resistance, binding property, and flexibility. Furthermore, it is related with the binder resin composition for non-aqueous secondary battery electrodes which can be used conveniently for the non-aqueous secondary battery excellent in charging / discharging cycling characteristics and high capacity | capacitance, and a lithium ion secondary battery.

  In recent years, due to advances in electronic technology, the performance of electronic devices has improved, and miniaturization and portability have progressed, and the demand for secondary batteries with high energy density as the power source has increased. Secondary batteries include, for example, nickel metal hydride secondary batteries, lithium ion secondary batteries, etc. These secondary batteries are also being developed for high-capacity and long-life products due to the miniaturization and weight reduction of equipment. .

  The electrode of the secondary battery is composed of an electrode active material, a conductive additive, and a binder that binds these to a current collector. Conventionally, fluororesins such as polyvinylidene fluoride and polytetrafluoroethylene have been frequently used for both positive and negative electrode binder resins for secondary batteries (Non-Patent Documents 1 and 2). However, in the secondary battery, since the positive electrode or the negative electrode repeats volume expansion and contraction during charge and discharge, the charge and discharge cycle life may be shortened by dropping of the active material and conductive agent. For this reason, the electrode binder is required to have cushioning properties and adhesion that can withstand the swelling and shrinkage of the electrode. However, the fluororesin has insufficient cushioning and adhesion that can follow the electrode. In addition, the fluororesin has a feature that it dissolves only in a specific solvent such as N-methylpyrrolidone, and there is a problem of adverse effects on the human body and the environment, such as a strange odor during electrode fabrication.

  With respect to these problems, in Patent Document 1, as a binder resin, from a polymer particle obtained by polymerizing a structural unit derived from an ethylenically unsaturated carboxylic acid monomer and a structural unit derived from an ethylenically unsaturated carboxylic acid monomer. By using the latex, the charge / discharge cycle characteristics at high temperature are excellent. However, this method is not necessarily sufficient in adhesion between the current collector and the binder.

  Patent Document 2 discloses that by using a polyamideimide resin as a binder resin, it is possible to create an electrode that is excellent in adhesion and bending to a metal and hardly causes cracking and peeling. However, although the polyamide-imide resin has tough properties, it is still a hard resin, and since it has low flexibility, it cannot be said that it has a sufficient effect on cracking and peeling. In addition, the polyamide-imide resin has a problem of using a solvent having a high environmental load at the time of electrode preparation, like the fluororesin.

Japanese Patent No. 4389282 Japanese Patent Laid-Open No. 1996-213048

"Battery Handbook" published by Denki Shoin 1980 "Industrial Materials" Nikkan Kogyo Shimbun, September 2008 (Vol.56, No.9)

  The present invention produces a non-aqueous secondary battery that has little adverse effect on the human body and the environment, has excellent adhesion to the current collector, and retains a high discharge capacity even in a high temperature environment due to repeated charge and discharge or heat generation. An object of the present invention is to provide a binder resin composition for a non-aqueous secondary battery electrode that can be used. Furthermore, a non-aqueous secondary battery electrode that has little influence on the electrode active material, secures current collection, improves its utilization efficiency, and can achieve battery charge / discharge cycle characteristics, high capacity, and An object is to provide a non-aqueous secondary battery using the electrode.

That is, in the first invention, a mixture containing a radically polymerizable ethylenically unsaturated monomer (A) and a polyamide resin (B) is used as an essential component in a surfactant, a polymerization initiator, and water. a method of manufacturing a in polymerized resin composition, polymerizing the average particle diameter of the (a) and the mixture was forced emulsification in the presence of a surfactant and water emulsion of (B) after the 2μm or less The present invention relates to a method for producing a binder resin composition for a non-aqueous secondary battery electrode.

In the second invention, the radically polymerizable ethylenically unsaturated monomer (A) is an alkoxysilyl group-containing ethylenically unsaturated monomer (c), an N-methylol group-containing ethylenically unsaturated monomer. The monomer (d) selected from the group (d) and at least one monomer selected from the group consisting of monomers (e) having two or more ethylenically unsaturated groups in one molecule The method for producing a binder resin composition for a non-aqueous secondary battery electrode according to the first invention, comprising 0.1 to 5% by weight in a total of 100% by weight of the total ethylenically unsaturated monomer About.

Further, in the third invention, the radically polymerizable ethylenically unsaturated monomer (A) is a carboxyl group-containing ethylenically unsaturated monomer (f), a sulfonic acid group-containing ethylenically unsaturated monomer ( g), phosphoric acid group-containing ethylenically unsaturated monomer (h), epoxy group-containing ethylenically unsaturated monomer (i), amide group-containing ethylenically unsaturated monomer (j), amino group-containing ethylene At least one monomer selected from the group consisting of the polymerizable unsaturated monomer (k) and the hydroxyl group-containing ethylenically unsaturated monomer (l) is a total of monomers selected from the group, It is related with the manufacturing method of the binder resin composition for non-aqueous secondary battery electrodes of 1st or 2nd invention characterized by including 0.1 to 50weight% in the total 100weight% of an unsaturated monomer.

The fourth invention is characterized in that the radically polymerizable ethylenically unsaturated monomer (A) comprises the carboxyl group-containing ethylenically unsaturated monomer (f) as an essential component. The manufacturing method of the binder resin composition for nonaqueous secondary battery electrodes of 3rd invention.

Moreover, 5th invention is a manufacturing method of the binder resin composition for non-aqueous secondary battery electrodes of any one of 1st-4th invention, wherein a polyamide resin (B) contains a polymeric fatty acid in the structure .

Further, the sixth invention relates to a process for the production of the first to fifth one of the nonaqueous secondary battery electrodes are use the resulting nonaqueous secondary battery electrode binder resin composition by the invention.

Furthermore, a seventh aspect of the present invention, a method for producing a nonaqueous secondary battery are use a sixth non-aqueous secondary battery electrode obtained by the present invention.

Furthermore, the eighth invention relates to the manufacturing method of the seventh invention, wherein the non-aqueous secondary battery is a lithium ion secondary battery.

  The binder resin composition for non-aqueous secondary battery electrodes of the present invention has excellent electrolytic solution resistance and excellent adhesion to the current collector, and the binder resin composition for non-aqueous secondary battery electrodes of the present invention By using it, it is possible to provide a long-life non-aqueous secondary battery that can reduce a reduction in discharge capacity in a charge / discharge cycle even in a high temperature environment due to repeated charge / discharge and heat generation.

<< ethylenically unsaturated monomer (A) >>
The radically polymerizable ethylenically unsaturated monomer (A) used in the present invention will be described.
The radically polymerizable ethylenically unsaturated monomer (A) used in the present invention includes an alkoxysilyl group-containing ethylenically unsaturated monomer (c) and an N-methylol group-containing ethylenically unsaturated monomer (d ) And at least one monomer selected from the group consisting of monomers (e) having two or more ethylenically unsaturated groups in one molecule, these self-crosslinking reactive functions The group is preferable because it can suppress the swelling / dissolution of the binder resin in the electrolytic solution and improve the resistance to the electrolytic solution by forming the particle internal cross-linking.
Alkoxysilyl group-containing ethylenically unsaturated monomer (c), N-methylol group-containing ethylenically unsaturated monomer (d), and monomer having two or more ethylenically unsaturated groups in one molecule At least one monomer selected from the group consisting of (e) is preferably used in an amount of 0.1 to 5% by weight in a total of 100% by weight of the whole ethylenically unsaturated monomer used for emulsion polymerization. . More preferably, it is 0.5 to 3% by weight. If the content is less than 0.1% by weight, the particles may not be sufficiently crosslinked, and the electrolytic solution resistance may deteriorate. On the other hand, if it exceeds 5% by weight, the polymerization stability during emulsion polymerization may decrease, the storage stability after polymerization may decrease, and the adhesion and charge / discharge cycle characteristics as a binder may also decrease. is there. In addition, a monomer containing an acidic group such as a carboxyl group as a monomer

  The alkoxysilyl group, N-methylol group, and ethylenically unsaturated group in the monomer (c), monomer (d), and monomer (e) are each self-polymerized mainly during emulsion polymerization. Although a crosslinked structure can be introduced into the resin particles produced by condensation or polymerization, a part of them may remain inside or on the surface after the emulsion polymerization. The remaining alkoxysilyl group, N-methylol group, and ethylenically unsaturated group contribute to the interparticle crosslinking of the resin particles of the binder composition. In particular, an alkoxysilyl group or an N-methylol group is preferable because it has an effect of contributing to an improvement in adhesion to the current collector. However, when the alkoxysilyl group-containing ethylenically unsaturated monomer (c) contains a large amount of acidic group or amino group-containing monomer, hydrolysis and condensation of the alkoxysilyl group is promoted, and the polymerization stability is lowered. Therefore, it is preferable to use the monomers (d) and (e).

  Examples of the alkoxysilyl group-containing ethylenically unsaturated monomer (c) include γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-methacryloxypropyltributoxysilane, and γ-methacryloxy. Propylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-acryloxypropylmethyldimethoxysilane, γ-methacryloxymethyltrimethoxysilane , Γ-acryloxymethyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltributoxysilane, vinylmethyldimethoxysilane and the like.

  Examples of the N-methylol group-containing ethylenically unsaturated monomer (d) include N-methylol (meth) acrylamide, N, N-di (methylol) acrylamide, and N-methylol-N-methoxymethyl (meth) acrylamide. And alkylol (meth) acrylamides.

Examples of the monomer (e) having two or more ethylenically unsaturated groups in one molecule include allyl (meth) acrylate, 1-methylallyl (meth) acrylate, and 2-methylallyl (meth) acrylate. 1-butenyl (meth) acrylate, 2-butenyl (meth) acrylate, 3-butenyl (meth) acrylate, 1,3-methyl-3-butenyl (meth) acrylate, 2- (meth) acrylate 2- Chloroallyl, 3-chloroallyl (meth) acrylate, o-allylphenyl (meth) acrylate, 2- (allyloxy) ethyl (meth) acrylate, allyl lactyl (meth) acrylate, citronellyl (meth) acrylate, (meth) Geranyl acrylate, rosinyl (meth) acrylate, cinnamyl (meth) acrylate, diallyl maleate, diallyl itaconic acid, A compound having a plurality of unequal ethylenically unsaturated groups such as (meth) vinyl acrylate, vinyl crotonate, vinyl oleate, vinyl linolenate, and 2- (2′-vinyloxyethoxy) ethyl (meth) acrylate. Saturated carboxylic acid esters;
Di (meth) acrylic acid ethylene glycol, di (meth) acrylic acid triethylene glycol, di (meth) acrylic acid tetraethylene glycol, tri (meth) acrylic acid trimethylolpropane, tri (meth) acrylic acid pentaerythritol, diacrylic acid Polyfunctional (meth) acrylic acid esters such as 1,1,1-trishydroxymethylethane, 1,1,1-trishydroxymethylethane triacrylate, 1,1,1-trishydroxymethylpropanetriacrylic acid;
Divinyls such as divinylbenzene and divinyl adipate;
Examples include diallyls such as diallyl isophthalate and diallyl phthalate.

The radically polymerizable ethylenically unsaturated monomer (A) includes a carboxyl group-containing ethylenically unsaturated monomer (f), a sulfonic acid group-containing ethylenically unsaturated monomer (g), and a phosphate group-containing ethylene. Unsaturated monomer (h), epoxy group-containing ethylenically unsaturated monomer (i), amide group-containing ethylenically unsaturated monomer (j), amino group-containing ethylenically unsaturated monomer (k) And at least one monomer selected from the group consisting of hydroxyl group-containing ethylenically unsaturated monomers (l) can improve physical properties such as adhesion to the current collector. In the monomers (f) to (l), the functional group tends to remain inside or on the surface even after the synthesis of the particles, and the adhesion effect to the current collector is large even in a small amount. Moreover, a part of them may be used for the crosslinking reaction, and by adjusting the degree of crosslinking of these functional groups, it is possible to balance the resistance to electrolytic solution and the adhesion. Among these monomers, a carboxyl group-containing ethylenically unsaturated monomer (f), a sulfonic acid group-containing ethylenically unsaturated monomer (g), and an amide group-containing ethylene are selected from the balance of polymerization stability and adhesion. The polymerizable unsaturated monomer (j) and the amino group-containing ethylenically unsaturated monomer (k) are preferable. Furthermore, the carboxyl group-containing ethylenically unsaturated monomer (f) is particularly preferable because it easily dissolves the polyamide resin (B), and as a result, the amount of the polyamide resin introduced can be increased.
These monomers (f) to (l) are preferably contained in an amount of 0.1 to 50% by weight in a total of 100% by weight of the whole ethylenically unsaturated monomer. The monomers (f) to (l) are better because they increase the polarity of the entire ethylenically unsaturated monomer and also have a role of dissolving the polyamide resin, more preferably 5 to 30% by weight. is there. More preferably, it is 10 to 30% by weight. When the amount of the monomers (f) to (l) is more than 50% by weight, the polar component is too much, so that the polymerization solution is thickened during the polymerization, the polymerization stability is lowered, and a water-soluble component is generated. The charge / discharge cycle characteristics may be degraded. If it is less than 0.1% by weight, the effect of improving adhesion and physical properties is small.

  Examples of the carboxyl group-containing ethylenically unsaturated monomer (f) include maleic acid, fumaric acid, itaconic acid, citraconic acid, or alkyl or alkenyl monoesters thereof, β- (meth) acryloxyethyl phthalate. Monoester, isophthalic acid β- (meth) acryloxyethyl monoester, terephthalic acid β- (meth) acryloxyethyl monoester, succinic acid β- (meth) acryloxyethyl monoester, acrylic acid, methacrylic acid, crotonic acid And cinnamic acid.

  Examples of the sulfonic acid group-containing ethylenically unsaturated monomer (g) include vinyl sulfonic acid, styrene sulfonic acid, tertiary butyl acrylamide sulfonic acid, allyl sulfonic acid, methallyl sulfonic acid, and butyl (meth) acrylate. 4-sulfonic acid, (meth) acrylooxybenzenesulfonic acid, etc. are mentioned.

As the phosphoric acid group-containing ethylenically unsaturated monomer (h), for example,
Diphenyl (2-acryloyloxyethyl) phosphate, diphenyl (2-methacryloyloxyethyl) phosphate, phenyl (2-acryloyloxyethyl) phosphate, acid phosphooxyethyl (meth) acrylate, acid phosphooxypropyl (meth) acrylate, (Meth) acryloyl oxyethyl acid phosphate monoethanolamine salt, 3-chloro-2-acid phosphooxypropyl (meth) acrylate, acid phosphooxypolyoxyethylene glycol mono (meth) acrylate, acid phosphooxypoly Examples thereof include oxypropylene glycol (meth) acrylate and allyl alcohol acid phosphate.

As the epoxy group-containing ethylenically unsaturated monomer (i), for example,
Glycidyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate glycidyl ether, glycidyl allyl ether, 2,3-epoxy-2-methylpropyl (meth) acrylate, 3,4-epoxycyclohexyl (meth) acrylate, 4-vinyl Examples thereof include epoxy group-containing unsaturated monomers such as -1-cyclohexene-1,2-epoxide, glycidyl cinnamate, 1,3-butadiene monoepoxide, and Celoxide 2000 (manufactured by Daicel Chemical Industries, Ltd.).

The amide group-containing ethylenically unsaturated monomer (j) in the present invention does not include N-methylol group-containing acrylamide. Examples of the amide group-containing ethylenically unsaturated monomer (j) excluding the N-methylol group-containing acrylamide include, for example, a first amide group-containing ethylenically unsaturated monomer such as (meth) acrylamide;
N-methoxymethyl- (meth) acrylamide, N-ethoxymethyl- (meth) acrylamide, N-propoxymethyl- (meth) acrylamide, N-butoxymethyl- (meth) acrylamide, N-pentoxymethyl- (meth) acrylamide Monoalkoxy (meth) acrylamides such as;
N, N-di (methoxymethyl) acrylamide, N-ethoxymethyl-N-methoxymethylmethacrylamide, N, N-di (ethoxymethyl) acrylamide, N-ethoxymethyl-N-propoxymethylmethacrylamide, N, N- Di (propoxymethyl) acrylamide, N-butoxymethyl-N- (propoxymethyl) methacrylamide, N, N-di (butoxymethyl) acrylamide, N-butoxymethyl-N- (methoxymethyl) methacrylamide, N, N- Dialkoxy (meth) acrylamides such as di (pentoxymethyl) acrylamide, N-methoxymethyl-N- (pentoxymethyl) methacrylamide;
Dialkyl (meth) acrylamides such as N, N-dimethylacrylamide and N, N-diethylacrylamide;
Examples include carbonyl group-containing (meth) acrylamides such as diacetone (meth) acrylamide.

As the amino group-containing ethylenically unsaturated monomer (k), for example,
Diethylamino group-containing ethylenic monomers such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, methylethylaminoethyl (meth) acrylate, acryloylmorpholine, dimethylaminopropyl (meth) acrylate, dimethylaminostyrene, diethylaminostyrene Saturated monomers;
Dialkylamino (meth) acrylamides such as N, N-dimethylaminopropylacrylamide, N, N-diethylaminopropylacrylamide;
Examples thereof include a salt generated by reacting the monomer with an acid.
Dialkylamino (meth) acrylamides can be expected to have both amino group and amide group effects. However, in order to utilize mainly the amino group effect, amino acid-containing ethylenically unsaturated monomers (k) are used. include.

The hydroxyl group-containing ethylenically unsaturated monomer (l) in the present invention does not include the N-methylol group-containing ethylenically unsaturated monomer (d). Examples of the hydroxyl group-containing ethylenically unsaturated monomer (l) include:
2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, glycerol mono (meth) acrylate, 4-hydroxyvinylbenzene, 1-ethynyl-1-cyclohexanol, allyl Examples include alcohol, polypropylene glycol (meth) acrylate, polytetramethylene glycol (meth) acrylate, and hexaethylene glycol (meth) acrylate.

The monomer that does not belong to the monomers (c) to (l) and can be used as the ethylenically unsaturated monomer (A) is not particularly limited,
For example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, pentyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, heptyl (meth) acrylate, hexyl ( (Meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) Acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate, icosyl (meth) acrylate Heneicosyl (meth) acrylate, docosyl (meth) acrylate, alkyl (meth) acrylates such as cyclohexyl (meth) acrylate, isobornyl (meth) acrylate;
Carbonyl group-containing unsaturated monomers such as vinyl methyl ketone, vinyl ethyl ketone, acetoacetoxyethyl acrylate, acetoacetoxypropyl acrylate, acetoacetoxybutyl acrylate, acetoacetoxyethyl methacrylate, acetoacetoxypropyl methacrylate, acetoacetoxybutyl methacrylate;
Perfluoromethylmethyl (meth) acrylate, perfluoroethylmethyl (meth) acrylate, 2-perfluorobutylethyl (meth) acrylate, 2-perfluorohexylethyl (meth) acrylate, 2-perfluorooctylethyl (meth) acrylate , 2-perfluoroisononylethyl (meth) acrylate, 2-perfluorononylethyl (meth) acrylate, 2-perfluorodecylethyl (meth) acrylate, perfluoropropylpropyl (meth) acrylate, perfluorooctylpropyl (meta ) Perfluoroalkyl having a C 1-20 perfluoroalkyl group such as acrylate, perfluorooctyl amyl (meth) acrylate, perfluorooctyl undecyl (meth) acrylate, etc. (Meth) acrylate;
Perfluoroalkyl group-containing ethylenically unsaturated monomers such as perfluoroalkylalkylenes such as perfluorobutylethylene, perfluorohexylethylene, perfluorooctylethylene, perfluorodecylethylene;
Methoxy polyethylene glycol (meth) acrylate, ethoxy polyethylene glycol (meth) acrylate, propoxy polyethylene glycol (meth) acrylate, n-butoxy polyethylene glycol (meth) acrylate, n-pentoxy polyethylene glycol (meth) acrylate, phenoxy polyethylene glycol (meta ) Acrylate, methoxy polypropylene glycol (meth) acrylate, ethoxy polypropylene glycol (meth) acrylate, propoxy polypropylene glycol (meth) acrylate, n-butoxy polypropylene glycol (meth) acrylate, n-pentoxy polypropylene glycol (meth) acrylate, phenoxy polypropylene Glycol (meth) acrylate, Carboxymethyl polytetramethylene glycol (meth) acrylate, phenoxy tetraethylene glycol (meth) acrylate, ethylenically unsaturated monomer having a polyether chain, such as methoxy hexaethylene glycol (meth) acrylate;
An ethylenically unsaturated monomer having a polyester chain such as a lactone-modified (meth) acrylate;
Fatty acid vinyl monomers such as vinyl acetate, vinyl butyrate, vinyl propionate, vinyl hexanoate, vinyl caprylate, vinyl laurate, vinyl palmitate, vinyl stearate;
Vinyl ether compounds such as butyl vinyl ether and ethyl vinyl ether;
Α-olefin monomers such as 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene and 1-hexadecene;
Allyl monomers such as allyl acetate, allylbenzene, allyl cyanide;
Vinyl monomers such as vinyl cyanide, vinylcyclohexane, vinylmethylketone, styrene, α-methylstyrene, 2-methylstyrene, chlorostyrene;
Examples include ethynyl monomers such as acetylene, ethynylbenzene, and ethynyltoluene. These may use only 1 type, or can mix and use 2 or more types.
When the ethylenically unsaturated monomer (A), which does not belong to the above-mentioned monomers (c) to (l), is used for a positive electrode material, it has an oxidation resistance because it is exposed to an oxidizing atmosphere. It is preferable to use a monomer having a low aromatic skeleton and no ether bond.

<< Polyamide resin (B) >>
Next, the polyamide resin (B) used in the present invention will be described.
Examples of the polyamide resin (B) include polycondensation of diamine and dicarboxylic acid, self-condensation of ω-amino-ω ′ carboxylic acid, and polycondensation of ω-amino-ω ′ carboxylic acid with diamine and / or dicarboxylic acid. Or a polyamide resin produced by a method such as ring-opening polymerization of a cyclic lactam. Here, dicarboxylic acid or monocarboxylic acid can be used as a polymerization regulator in the polycondensation or ring-opening polymerization.

  Specific examples of the diamine used in the production of the polyamide resin (B) include ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, 1,7-diaminoheptane, 1,8-diaminooctane, Examples include 1,9-diaminononane, 1,10-diaminodecane, phenylenediamine, and metaxylylenediamine.

  Specific examples of the dicarboxylic acid used in the production of the polyamide resin (B) include glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, nonanedicarboxylic acid, decanedicarboxylic acid, tetradecanedicarboxylic acid, and octadecane. And dicarboxylic acid, fumaric acid, phthalic acid, xylylene dicarboxylic acid and dimer acid (unsaturated dicarboxylic acid having 36 carbon atoms synthesized from unsaturated fatty acid mainly composed of linoleic acid and oleic acid).

  Specific examples of the ω-amino-ω ′ carboxylic acid used for the production of the polyamide resin (B) include 6-aminocaproic acid, 7-aminoheptanoic acid, 9-aminononanoic acid, 11-aminoundecanoic acid and 12-amino. Examples include dodecanoic acid.

  Specific examples of the cyclic lactam used for the production of the polyamide resin (B) include ε-caprolactam, ω-enantolactam, and ω-lauryl lactam.

Specific examples of the dicarboxylic acid used as the polymerization regulator include glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid, as in the dicarboxylic acid used in the production of the polyamide resin (B). Nonanedicarboxylic acid, decanedicarboxylic acid, tetradecanedicarboxylic acid, octadecanedicarboxylic acid, fumaric acid, phthalic acid, xylylene dicarboxylic acid, and dimer acid.
Specific examples of the monocarboxylic acid include caproic acid, heptanoic acid, nonanoic acid, undecanoic acid, and dodecanoic acid.

In the present invention, among the polyamide resins obtained by the above-described method, the polyamide resin produced using dimer acid as the dicarboxylic acid has an ethylenically unsaturated monomer (A) due to the dimer acid-derived hydrophobic skeleton. This is preferable because the compatibility with the resin can be increased, the amount of polyamide resin introduced can be increased, and as a result, higher adhesion can be obtained. From the same point of view, the lower the molecular weight of the polyamide resin, the higher the compatibility. Therefore, the number average molecular weight is preferably 800 to 10,000, and more preferably 1,000 to 5,000. Commercially available products of polyamide resins produced using dimer acid include the tomide series manufactured by T & K TOKA Corporation, the macromelt series manufactured by Henkel Japan Co., Ltd., and the new amide series manufactured by Harima Kasei Co., Ltd.
In addition, when used as a positive electrode material, the material is exposed to an oxidizing atmosphere, and therefore does not include an unsaturated double bond site-[NH (CH ₂ ) ₅ CO]-,-[NH (CH ₂ ) ₆ NHCO (CH ₂ ) ₄ CO] —, — [NH (CH ₂ ) ₆ NHCO (CH ₂ ) ₈ CO] —, — [NH (CH ₂ ) _{1 0} CO] —, — [NH (CH ₂ ) _{1 1} CO]-and-[NH (CH ₂ ) ₂ NHCO-DCO]-
A polyamide resin having as a structural unit at least one selected from the group consisting of (wherein D represents a hydrocarbon group having 34 carbon atoms in the hydrogenated dimer acid molecule) is preferably used.

  Specific examples thereof include 6-nylon, 66-nylon, 610-nylon, 11-nylon, 12-nylon, 6/66 copolymer nylon, 6/610 copolymer nylon, 6/11 copolymer nylon, 6 / 12 copolymer nylon, 6/66/11 copolymer nylon, 6/66/12 copolymer nylon, 6/66/11/12 copolymer nylon, 6/66/610/11/12 copolymer nylon and hydrogenated dimer Examples include acid-based polyamide resins. These polymers or copolymers may be used alone or in combination of two or more.

The weight ratio of the ethylenically unsaturated monomer (A) and the polyamide resin (B) is preferably (A) / (B) = 99/1 to 10/90, and preferably 95/5 to 60/40. It is more preferable.
When the weight ratio of the ethylenically unsaturated monomer (A) is more than 99% by weight, the polyamide resin (B) is relatively too small, so that improvement in adhesion cannot be expected. On the other hand, when the weight ratio of the ethylenically unsaturated monomer (A) is less than 10% by weight, the polymerizability of the emulsified component consisting of the ethylenically unsaturated monomer (A) and the polyamide resin (B) becomes poor. And it becomes difficult to emulsify.

  As the emulsifier used in the emulsion polymerization in the present invention, a surfactant is used, such as a reactive surfactant having an ethylenically unsaturated group or a non-reactive surfactant having no ethylenically unsaturated group, A conventionally well-known thing can be used arbitrarily.

  Reactive surfactants having an ethylenically unsaturated group can be further broadly classified into anionic and nonionic nonionic ones. In particular, when an anionic reactive surfactant or a nonionic reactive surfactant having an ethylenically unsaturated group is used, the dispersion particle size of the copolymer becomes fine and the particle size distribution becomes narrow. When used as a binder for battery electrodes, it is possible to improve the resistance to electrolytic solution, which is preferable. This anionic reactive surfactant or nonionic reactive surfactant having an ethylenically unsaturated group may be used singly or in combination.

Specific examples of the anionic reactive surfactant having an ethylenically unsaturated group are shown below, but the surfactants that can be used in the present invention are limited to those described below. It is not a thing. Examples of the surfactant include alkyl ethers (commercially available products include, for example, Aqualon KH-05, KH-10, KH-20, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., ADEKA rear soap SR-10N, SR manufactured by ADEKA Corporation. -20N, LATEMUL PD-104 manufactured by Kao Corporation), etc .;
Sulfosuccinic acid ester-based (for example, LATEMUL S-120, S-120A, S-180P, S-180A, Sanyo Chemical Co., Ltd., Elemiol JS-2, etc., manufactured by Kao Corporation);
Alkyl phenyl ether type or alkyl phenyl ester type (commercially available products include, for example, Aqualon H-2855A, H-3855B, H-3855C, H-3856, HS-05, HS-10, HS, manufactured by Daiichi Kogyo Seiyaku Co., Ltd. -20, HS-30, Adeka Soap SDX-222, SDX-223, SDX-232, SDX-233, SDX-259, SE-10N, SE-20N, etc. manufactured by ADEKA Corporation);
(Meth) acrylate sulfate-based (commercially available products include, for example, Antox MS-60, MS-2N, Sanyo Chemical Industries Co., Ltd., Elemiol RS-30, manufactured by Nippon Emulsifier Co., Ltd.);
Examples of the phosphoric acid ester (commercially available products include H-3330PL manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Adeka Soap PP-70 manufactured by ADEKA Co., Ltd., etc.)

Nonionic reactive surfactants that can be used in the present invention include, for example, alkyl ethers (commercially available products such as Adeka Soap ER-10, ER-20, ER-30, and ER- manufactured by ADEKA Corporation). 40, Latemu PD-420, PD-430, PD-450, etc. manufactured by Kao Corporation);
Alkyl phenyl ether type or alkyl phenyl ester type (commercially available products include, for example, Aqualon RN-10, RN-20, RN-30, RN-50, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., ADEKA rear soap NE- manufactured by ADEKA Co., Ltd. 10, NE-20, NE-30, NE-40, etc.);
(Meth) acrylate sulfate esters (commercially available products include, for example, RMA-564, RMA-568, and RMA-1114 manufactured by Nippon Emulsifier Co., Ltd.).

  When the binder composition of the present invention is obtained by emulsion polymerization, a non-reactive surfactant having no ethylenically unsaturated group can be used in addition to the above-described reactive surfactant having an ethylenically unsaturated group. . Non-reactive surfactants can be broadly classified into non-reactive anionic surfactants, non-reactive cationic surfactants and non-reactive nonionic surfactants.

Examples of non-reactive nonionic surfactants include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether and polyoxyethylene stearyl ether;
Polyoxyethylene alkylphenyl ethers such as polyoxyethylene octylphenyl ether and polyoxyethylene nonylphenyl ether;
Sorbitan higher fatty acid esters such as sorbitan monolaurate, sorbitan monostearate, sorbitan trioleate;
Polyoxyethylene sorbitan higher fatty acid esters such as polyoxyethylene sorbitan monolaurate;
Polyoxyethylene higher fatty acid esters such as polyoxyethylene monolaurate and polyoxyethylene monostearate;
Glycerin higher fatty acid esters such as oleic acid monoglyceride and stearic acid monoglyceride;
Examples include polyoxyethylene / polyoxypropylene / block copolymer, polyoxyethylene distyrenated phenyl ether, and the like.

Examples of non-reactive anionic surfactants include higher fatty acid salts such as sodium oleate;
Alkylaryl sulfonates such as sodium dodecylbenzenesulfonate;
Alkyl sulfate salts such as sodium lauryl sulfate;
Polyoxyethylene alkyl ether sulfate esters such as sodium polyoxyethylene lauryl ether sulfate;
Polyoxyethylene alkylaryl ether sulfate salts such as sodium polyoxyethylene nonylphenyl ether sulfate;
Alkyl sulfosuccinic acid ester salts such as sodium monooctyl sulfosuccinate, sodium dioctyl sulfosuccinate, sodium polyoxyethylene lauryl sulfosuccinate and derivatives thereof;
Examples thereof include polyoxyethylene distyrenated phenyl ether sulfate salts.

Examples of non-reactive cationic surfactants include
For example, alkyltrimethylamine-based quaternary ammonium salts represented by RN (CH ₃ ) ₃ X [R = stearyl, cetyl, lauryl, oleyl, dodecyl, palm, soybean, beef tallow etc./X=halogen, amine, etc.];
Quaternary ammonium salts such as tetramethylamine salts and tetrabutylamine salts;
Acetates represented by (RNH ₃ ) (CH ₃ COO) [R = stearyl, cetyl, lauryl, oleyl, dodecyl, palm, soybean, beef tallow, etc.];
Benzylamine quaternary ammonium salts such as lauryldimethylbenzylammonium salt (halogen / amine salt, etc.), stearyldimethylbenzylammonium salt (halogen / amine salt, etc.), dodecyldimethylbenzylammonium salt (halogen / amine salt, etc.);
_{R (CH 3) N (C} 2 H 4 O) mH (C 2 H 4 O) n · X [R = stearyl cetyl lauryl oleyl dodecyl coconut, soybean beef tallow / X = halogen amine , M, and n are integers of 0 or more], and polyoxyalkylene-based quaternary ammonium salts can be used.

  The amount of the surfactant used in the present invention is not necessarily limited, and can be appropriately selected according to the physical properties required when the binder resin composition is finally used as a binder for non-aqueous secondary battery electrodes. . For example, the surfactant is usually preferably 0.1 to 30 parts by weight, more preferably 0.3 to 20 parts by weight with respect to 100 parts by weight of the total of ethylenically unsaturated monomers, More preferably, it is in the range of 0.5 to 10 parts by weight.

In the emulsion polymerization for obtaining the binder resin composition of the present invention, a water-soluble protective colloid can be used in combination. Examples of the water-soluble protective colloid include polyvinyl alcohols such as partially saponified polyvinyl alcohol, fully saponified polyvinyl alcohol, and modified polyvinyl alcohol;
Cellulose derivatives such as hydroxyethylcellulose, hydroxypropylcellulose, carboxymethylcellulose salts;
Natural polysaccharides such as guar gum and the like can be mentioned, and these can be used either alone or in combination. The amount of the water-soluble protective colloid used is 0.1 to 5 parts by weight, more preferably 0.5 to 2 parts by weight, based on 100 parts by weight of the total amount of ethylenically unsaturated monomers.

  Examples of the aqueous medium used in the emulsion polymerization for obtaining the binder resin composition of the present invention include water, and a hydrophilic organic solvent can be used as long as the object of the present invention is not impaired.

The polymerization initiator used for obtaining the binder composition of the present invention is not particularly limited as long as it has the ability to initiate radical polymerization, and a known oil-soluble polymerization initiator or water-soluble polymerization initiator is used. be able to. The oil-soluble polymerization initiator is not particularly limited, and examples thereof include benzoyl peroxide, tert-butyl peroxybenzoate, tert-butyl hydroperoxide, tert-butyl peroxy (2-ethylhexanoate), and tert-butyl peroxide. Organic peroxides such as oxy-3,5,5-trimethylhexanoate, di-tert-butyl peroxide;
2,2′-azobisisobutyronitrile, 2,2′-azobis-2,4-dimethylvaleronitrile, 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 1,1 Mention may be made of azobis compounds such as' -azobis-cyclohexane-1-carbonitrile. These may use only 1 type or can mix and use 2 or more types. These polymerization initiators are preferably used in an amount of 0.1 to 10.0 parts by weight with respect to 100 parts by weight of the ethylenically unsaturated monomer.

In the present invention, it is preferable to use a water-soluble polymerization initiator. For example, ammonium persulfate, potassium persulfate, hydrogen peroxide, 2,2′-azobis (2-methylpropionamidine) dihydrochloride and the like are conventionally known. A thing can be used conveniently. Moreover, when performing emulsion polymerization, a reducing agent can be used together with a polymerization initiator if desired. Thereby, it becomes easy to accelerate the emulsion polymerization rate or to perform the emulsion polymerization at a low temperature. Examples of such a reducing agent include reducing organic compounds such as metal salts such as ascorbic acid, ersorbic acid, tartaric acid, citric acid, glucose, formaldehyde sulfoxylate, sodium thiosulfate, sodium sulfite, sodium bisulfite, Examples include reducing inorganic compounds such as sodium bisulfite, ferrous chloride, Rongalite, thiourea dioxide, and the like. These reducing agents are preferably used in an amount of 0.05 to 5.0 parts by weight with respect to 100 parts by weight of the total ethylenically unsaturated monomer. In addition, it can superpose | polymerize also by a photochemical reaction, radiation irradiation, etc. irrespective of an above described polymerization initiator. The polymerization temperature is not less than the polymerization start temperature of each polymerization initiator. For example, in the case of a peroxide-based polymerization initiator, it may be usually about 70 ° C. The polymerization time is not particularly limited, but is usually 2 to 24 hours.

  Further, if necessary, sodium acetate, sodium citrate, sodium bicarbonate, etc. as a buffering agent, and octyl mercaptan, 2-ethylhexyl thioglycolate, octyl thioglycolate, stearyl mercaptan, lauryl mercaptan as chain transfer agents A suitable amount of mercaptans such as t-dodecyl mercaptan can be used.

  The average particle size of the binder resin composition is preferably 10 to 1000 nm, and more preferably 30 to 600 nm, from the viewpoint of the binding property of the electrode active material and the stability of the particles. Further, when a large amount of coarse particles exceeding 1000 nm are contained, the stability of the particles is impaired. Therefore, the coarse particles exceeding 1000 nm are preferably at most 5% by weight. In addition, the average particle diameter in the present invention represents a volume average particle diameter and can be measured by a dynamic light scattering method.

  The average particle diameter can be measured by the dynamic light scattering method as follows. The resin fine particle dispersion is diluted with water 200 to 1000 times according to the solid content. About 5 ml of the diluted solution is injected into a cell of a measuring apparatus [Microtrack manufactured by Nikkiso Co., Ltd.], and the measurement is performed after inputting the solvent (water in the present invention) and the refractive index condition of the resin according to the sample. The peak of the volume particle size distribution data (histogram) obtained at this time is defined as the average particle size of the present invention.

In the binder resin composition for non-aqueous secondary battery electrodes containing the resin fine particle dispersion of the present invention, a film forming aid, an antifoaming agent, a leveling agent, a preservative, a pH adjusting agent, a viscosity adjusting agent and the like are required. Can be blended.

  The film-forming aid is responsible for the temporary plasticization function that helps the formation of the coating film and evaporates relatively quickly after the coating film is formed, thereby improving the strength of the coating film. Is preferably a solvent having a temperature of 110 to 200 ° C. Specifically, propylene glycol monobutyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol monobutyl ether, diethylene glycol diethyl ether, dipropylene glycol monopropyl ether, carbitol, butyl carbitol, dibutyl carbitol, benzyl alcohol, etc. Is mentioned. Among these, ethylene glycol monobutyl ether and propylene glycol monobutyl ether are particularly preferable because they have a high film forming auxiliary effect in a small amount. These film forming aids are preferably contained in the binder composition in an amount of 0.5 to 15% by weight.

  The viscosity modifier may be used in an amount of 1 to 100 parts by weight with respect to 100 parts by weight of the resin fine particle dispersion. Examples of the viscosity modifier include carboxymethylcellulose, methylcellulose, hydroxymethylcellulose, ethylcellulose, polyvinyl alcohol, polyacrylic acid (and its salt), oxidized starch, phosphorylated starch, and casein.

  The binder resin composition for nonaqueous secondary battery electrodes of the present invention can be used for forming a positive electrode and a negative electrode of a secondary battery. In addition, it can also be used for energy devices, that is, capacitors, solar cells and the like.

  The binder resin composition for a non-aqueous secondary battery electrode of the present invention can produce a non-aqueous secondary battery electrode by blending an electrode active material, applying it to a current collector, and drying.

  In the present invention, the binder resin composition for a non-aqueous secondary battery electrode is usually 0.1 to 20 parts by weight, preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the electrode active material, as its solid content. Used. If the amount is less than 0.1 part by weight, the force for binding the electrode active material to the current collector is insufficient, and the electrode active material may fall off and the battery capacity may decrease. On the other hand, if the binder composition exceeds 20 parts by weight, the resistance in the battery may increase and the capacity of the battery may decrease.

A method of forcibly emulsifying a mixture containing an ethylenically unsaturated monomer (A) and a polyamide resin (B) used in the present invention in the presence of a surfactant and water so that the average particle size of the emulsion is 2 μm or less. Will be described.
As the preparation method of each component, the polyamide resin (B) is added to the radically polymerizable ethylenically unsaturated monomer (A), and after dissolving or dispersing (B), the surfactant and water are added and stirred. Thus, it is preferable to prepare a pre-emulsified product and then perform forced emulsification. When the polyamide resin (B) is added to a mixture of the monomer (A), surfactant and water, it takes a long time to dissolve or disperse (B), which is not preferable.

  The method for forcibly emulsifying the preliminary emulsion is not particularly limited, and according to known equipment such as a homomixer, a high-pressure homogenizer, an ultrasonic disperser, a line flow mixer, a rotor / stator continuous disperser and the like. What is necessary is just to perform an emulsification process until the average particle diameter of an emulsion becomes 2 micrometers or less using these. If the average particle diameter exceeds 2 μm, there are many aggregates in the polymerization reaction, the mechanical stability of the binder resin composition is inferior, and the charge / discharge cycle characteristics of the battery electrode obtained from the polymer are insufficient. Therefore, it is not preferable. After preparing the above emulsion having an average particle size of 2 μm or less, polymerization is carried out in the presence of a polymerization initiator. As a method for this, polymerization may be started by charging the emulsion in a reaction vessel in its entirety. In addition, after part of the reaction vessel is charged and the polymerization is started, it may be added in several divided portions, or after a part of the reaction vessel is charged and the polymerization is started, the rest may be dropped, or in advance Water and a part of the surfactant as necessary may be charged into the reaction vessel, and the whole amount may be dropped.

  As a method for adding the polymerization initiator, the whole amount may be charged in the reaction vessel in advance, or the whole amount may be added after the temperature is raised, and a part of the polymerization initiator is charged in the reaction vessel and the polymerization is further started several times. It may be divided and added in portions, a part may be charged into the reaction vessel and the polymerization may be started, and the remainder may be added dropwise, or the entire amount may be added dropwise. When the polymerization initiator is added or dropped in portions, it may be added or dropped into the reaction vessel alone, or may be added or dropped in a state of being mixed with the emulsion. In addition, after adding a polymerization initiator by these methods, a polymerization initiator may be additionally added once or twice or more for the purpose of increasing the reaction rate.

  As described above, the polymer derived from the monomer (A) is obtained by performing radical polymerization in a state where the polyamide resin (B) is dissolved and dispersed in the radically polymerizable ethylenically unsaturated monomer (A). Takes an IPN (Inter-penetrating Network) structure in which each cross-linked network penetrates each other, or a semi-IPN structure in which one cross-links into the other cross-linked network. Thus, adhesion, electrolyte solution resistance, and charge / discharge cycle characteristics superior to simple polymer blends and cross-linking of polymers can be obtained.

Examples of the electrode active material include the following.
The positive electrode active material is not particularly limited, and metal oxides that can be doped or intercalated with lithium ions, metal compounds such as metal sulfides, conductive polymers, and the like can be used. Examples thereof include transition metal oxides such as Fe, Co, Ni, and Mn, composite oxides with lithium, and inorganic compounds such as transition metal sulfides. Specifically, transition metal oxide powders such as MnO, V ₂ O ₅ , V ₆ O ₁₃ , TiO ₂ , layered structure lithium nickelate, lithium cobaltate, lithium manganate, spinel structure lithium manganate, etc. Examples thereof include composite oxide powders of lithium and transition metals, lithium iron phosphate materials that are phosphate compounds having an olivine structure, transition metal sulfide powders such as TiS ₂ and FeS, and the like. In addition, conductive polymers such as polyaniline, polyacetylene, polypyrrole, and polythiophene can also be used. Moreover, you may mix and use said inorganic compound and organic compound.
The negative electrode active material is not particularly limited as long as it can be doped or intercalated with lithium ions. For example, metal Li, alloys thereof such as tin alloy, silicon alloy, lead alloy, Li _X Fe ₂ O ₃ , Li _X Fe ₃ O ₄ , Li _X WO ₂ , lithium titanate, lithium vanadate, silicon Metal oxides such as lithium oxide, conductive polymers such as polyacetylene and poly-p-phenylene, amorphous carbonaceous materials such as soft carbon and hard carbon, artificial graphite such as highly graphitized carbon materials, or natural Examples thereof include carbonaceous powders such as graphite, carbon black, mesophase carbon black, resin-fired carbon materials, air-growth carbon fibers, and carbon fibers.
These negative electrode active materials can be used alone or in combination.

  Examples of the conductive material used in combination with the electrode active material include nickel powder, cobalt oxide, titanium oxide, and carbon. Examples of carbon include acetylene black, furnace black, graphite, carbon fiber, and fullerenes. As for the usage-amount of an electroconductive material, 0.5-10 weight part is preferable with respect to 100 weight part of electrode active materials. If the amount is less than 0.5 part by weight, the conductivity is low, and the capacity when charging / discharging at a high rate of the secondary battery may decrease. The current collector is not particularly limited as long as it is usually used for a secondary battery electrode, and examples thereof include punching metal, expanded metal, wire mesh, foam metal, and reticulated metal fiber sintered body. .

  In order to form a non-aqueous secondary battery electrode, the binder resin composition for a non-aqueous secondary battery electrode is applied to a current collector in the form of a slurry, heated and dried. As a coating method, any coater head such as a reverse roll method, a comma bar method, a gravure method, an air knife method, etc. can be used, and as a drying method, a standing drying, a blow dryer, a hot air dryer, an infrared heater, a far-infrared heater, An infrared heater can be used.

The non-aqueous secondary battery of the present invention comprises a secondary battery electrode manufactured using the binder resin composition for a non-aqueous secondary battery electrode. When producing a non-aqueous secondary battery using the non-aqueous secondary battery electrode obtained as described above, for example, a carbonate solvent such as ethylene carbonate or propylene carbonate is used as the electrolyte, and LiPF ₆ is used as the electrolyte. It is preferable to use it as a lithium ion secondary battery using a lithium ion compound such as. Furthermore, a battery is configured using components such as a separator, a current collector, a terminal, and an insulating plate. Examples of the separator include polyethylene nonwoven fabric, polypropylene nonwoven fabric, polyamide nonwoven fabric, and those obtained by subjecting them to hydrophilic treatment.

  EXAMPLES The present invention will be described more specifically with reference to the following examples. However, the following examples do not limit the scope of rights of the present invention. In the examples, “part” represents “part by weight” and “%” represents “% by weight”.

[Preparation of resin fine particle water dispersion]
[Production Example 1]
To a mixture of 40 parts of 2-ethylhexyl acrylate and 60 parts of styrene, 5 parts of tomide TPAE-826-5A [manufactured by T & K TOKA Co., Ltd.] as a polyamide resin was added and stirred to dissolve.
In addition to this, 1.6 parts of "Aqualon KH-10" manufactured by Daiichi Kogyo Seiyaku Co., Ltd. as a reactive ammonia neutralizing anionic surfactant was added to 80 parts of deionized water,
A preliminary emulsion having an average particle size of 40 μm was obtained by stirring. The average particle size was measured using “Mastersizer 2000” manufactured by Malvern Instruments Ltd.
The preliminary emulsion was forcibly emulsified with a homomixer at 12000 rpm for 20 minutes to obtain a pre-emulsion having an average particle size of 1.6 μm.
Separately, in a reaction vessel equipped with a stirrer, a thermometer, a dropping funnel, and a refluxing vessel, 140 parts of ion exchange water and 0.4 part of Aqualon KH-10 as a surfactant were charged, and 5% of the pre-emulsion was added. Added further. After raising the internal temperature to 70 ° C. and sufficiently purging with nitrogen, 6 parts of a 5% aqueous solution of potassium persulfate was added to initiate polymerization. After maintaining the inside of the reaction system at 70 ° C. for 5 minutes, the remaining pre-emulsion was added dropwise over 3 hours while maintaining the internal temperature at 80 ° C., and stirring was further continued for 2 hours. After confirming that the conversion rate exceeded 98% by solid content measurement, the temperature was cooled to 30 ° C. to obtain an aqueous dispersion of resin fine particles.

[Production Examples 2 to 17]
The compounding compositions shown in Table 1 were synthesized in the same manner as in Production Example 1 to obtain resin fine particle aqueous dispersions in Production Examples 2 to 17.

[Production Example 18]
To a mixture of 40 parts of 2-ethylhexyl acrylate, 44.5 parts of styrene, 0.5 part of N-methylolacrylamide and 15 parts of acrylic acid, 10 parts of tomide 509 as a polyamide resin was added and stirred to dissolve.
In addition to this, 1.6 parts of "Aqualon KH-10" manufactured by Daiichi Kogyo Seiyaku Co., Ltd. as a reactive ammonia neutralizing anionic surfactant was added to 80 parts of deionized water,
A pre-emulsion with an average particle size of 40 μm was obtained by stirring.
Separately, in a reaction vessel equipped with a stirrer, a thermometer, a dropping funnel, and a refluxing vessel, 140 parts of ion exchange water and 0.4 part of Aqualon KH-10 as a surfactant were charged, and 5% of the pre-emulsion was added. Added further. After raising the internal temperature to 70 ° C. and sufficiently purging with nitrogen, 6 parts of a 5% aqueous solution of potassium persulfate was added to initiate polymerization. After maintaining the inside of the reaction system at 70 ° C. for 5 minutes, the remaining pre-emulsion was added dropwise over 3 hours while maintaining the internal temperature at 80 ° C., and stirring was further continued for 2 hours. After confirming that the conversion rate exceeded 98% by solid content measurement, the temperature was cooled to 30 ° C. to obtain an aqueous dispersion of resin fine particles.

Tomide TPAE-828-5A: T & K TOKA Co., Ltd. dimer acid-derived polyamide resin (containing unsaturated groups)
Tomide 509: Dimer acid-derived polyamide resin (containing unsaturated groups) manufactured by T & K TOKA
Tomide 1340: Polyamide resin derived from heavy dimer acid (containing unsaturated groups) manufactured by T & K TOKA
Toresin F-30K: Polyamide resin (not containing unsaturated groups) manufactured by Nagase ChemteX Corporation
Amilan CM4000: Polyamide resin (not containing unsaturated groups) manufactured by Toray Industries, Inc.
Catiogen TMP: surfactant (cetyltrimethylammonium chloride) manufactured by Daiichi Kogyo Seiyaku Co., Ltd.
V-50: Wako Pure Chemical Industries, Ltd. 2,2'-azobis (2-amidinopropane) dihydrochloride

[Production Example 19]
To 100 parts by weight of the solid content of the resin fine particle aqueous dispersion obtained in Production Example 17, 40 parts by weight of solid resin FS-250E5AS manufactured by Nagase Chemtex Co., Ltd., which is a water-dispersed polyamide resin, is added and stirred. A resin fine particle dispersion was obtained.

(Polymerization stability)
Each resin fine particle dispersion obtained in Production Examples 1 to 17 was filtered with a 100 mesh filter cloth, and the dry weight of the residue remaining on the filter cloth was evaluated according to the following criteria.
○ = less than 0.1 g / kg resin fine particle dispersion Δ = 0.1 g or more to less than 1.0 g / kg resin fine particle dispersion × = 1.0 g or more per kg resin fine particle dispersion

[Creation of non-aqueous secondary battery electrode]
[Examples 1-16, Comparative Examples 1-3]
(Preparation of positive electrode)
3 parts as solid content of the resin fine particle aqueous dispersions obtained in Production Examples 1 to 19, 90 parts of lithium iron phosphate (LiFePO ₄ ) as a positive electrode active material, 5 parts of acetylene black as a conductive material, thickener Then, 2 parts of carboxymethylcellulose was added, ion-exchanged water was added so that the solid content was 50%, and then kneaded to prepare a composition for a secondary battery electrode. This secondary battery electrode composition was applied onto a 20 μm-thick aluminum foil serving as a current collector using a doctor blade, dried under reduced pressure, and subjected to a rolling process using a roll press to form a 50 μm-thick positive electrode composite. A positive electrode having an agent layer was produced.

(Preparation of negative electrode)
2 parts as a solid content of the resin fine particle aqueous dispersions obtained in Production Examples 1 to 19, 97 parts of mesophase carbon as a negative electrode active material, and 1 part of carboxymethyl cellulose as a thickener are added so that the solid content is 50%. After adding ion exchange water, it knead | mixed and the binder composition was adjusted. After applying this binder composition onto a copper foil having a thickness of 20 μm as a current collector using a doctor blade, drying under reduced pressure, performing a rolling process by a roll press, and having a negative electrode mixture layer having a thickness of 50 μm A negative electrode was produced.

[Comparative Example 4]
(Preparation of positive electrode)
5 parts of KF polymer W # 1100 (polyvinylidene fluoride manufactured by Kureha Co., Ltd.) as a solid content, 90 parts of lithium iron phosphate (LiFePO ₄ ) as a positive electrode active material, and 5 parts of acetylene black as a conductive material are added, N-methyl-2-pyrrolidone was added so as to have a solid content of 50%, and then kneaded to prepare a composition for a secondary battery electrode. This secondary battery electrode composition was applied onto a 20 μm-thick aluminum foil serving as a current collector using a doctor blade, dried under reduced pressure, and subjected to a rolling process using a roll press to form a 50 μm-thick positive electrode composite. A positive electrode having an agent layer was produced.

(Preparation of negative electrode)
3 parts of KF polymer W # 1100 (polyvinylidene fluoride manufactured by Kureha Co., Ltd.) as a solid content and 97 parts of mesophase carbon as a negative electrode active material are added, and N-methyl-2-pyrrolidone is added so that the solid content is 50%. Then, the composition for secondary battery electrodes was prepared by kneading. This secondary battery electrode composition was applied onto a 20 μm thick copper foil serving as a current collector using a doctor blade, dried under reduced pressure, and subjected to a rolling process using a roll press to form a negative electrode composite having a thickness of 50 μm. A negative electrode having an agent layer was produced.

<Assembly of lithium secondary battery positive electrode evaluation cell>
The positive electrode produced previously was punched into a diameter of 16 mm, the working electrode was a metallic lithium foil, a separator made of a porous polypropylene film was inserted between the working electrode and the counter electrode, and an electrolyte solution (ethylene carbonate and diethyl carbonate was added). A coin cell was assembled by filling a mixed solvent mixed at a ratio of 1: 1 (volume ratio) with a nonaqueous electrolytic solution in which LiPF ₆ was dissolved at a concentration of 1M. The coin cell was assembled in a glove box substituted with argon gas, and a predetermined battery characteristic evaluation was performed after the cell assembly.

<Assembly of lithium secondary battery negative electrode evaluation cell>
The negative electrode prepared earlier was punched to a diameter of 16 mm, the metal lithium foil was the counter electrode, a separator made of a porous polypropylene film was inserted between the working electrode and the counter electrode, and an electrolyte solution (ethylene carbonate and diethyl carbonate was added). A coin cell was assembled by filling a mixed solvent mixed at a ratio of 1: 1 (volume ratio) with a nonaqueous electrolytic solution in which LiPF ₆ was dissolved at a concentration of 1M. The coin cell was assembled in a glove box substituted with argon gas, and a predetermined battery characteristic evaluation was performed after the cell assembly.

  Using the secondary battery electrode and lithium secondary battery electrode evaluation cell obtained by the above method, adhesion, resistance to electrolytic solution, and battery characteristics were evaluated.

(Adhesion)
Using a knife on the electrode surface, 6 incisions were made from the mixture layer to the depth reaching the current collector, both vertically and horizontally at intervals of 2 mm, to make a grid cut. An adhesive tape was applied to the cut and immediately peeled off, and the degree of the active material falling off was determined by visual judgment. The evaluation criteria are shown below. The evaluation results are shown in Table 2.
A: “No peeling”
○: “Slightly peeled off (a level with no practical problem)”
○ △: About half peel (problem but usable level)
Δ: “Peeling at most parts”
×: “Completely peeled”

(Electrolytic solution resistance)
The prepared electrode was immersed in a mixed solvent in which ethylene carbonate and diethyl carbonate were mixed at a ratio of 1: 1 (volume ratio) at 60 ° C. for 24 hours, and the swelling state of the film and the elution state of the resin before and after immersion were as follows: Calculation and comparative evaluation were performed.
Swelling ratio (%) = [(weight after immersion) / (weight before immersion)] × 100
Dissolution rate (%) = [1- (weight after immersion drying) / (weight before immersion)] × 100
As the swelling rate is closer to 100% and the dissolution rate is closer to 0%, the resistance to electrolytic solution is higher. The evaluation results are shown in Table 2.
○: “Swelling rate is less than 110%. No problem at all”
Δ: “The swelling ratio is 110% or more and less than 120. Practical use is possible.”
X: “Swelling rate is 120% or more.

○: “Elution rate is less than 1.0%. No problem”
Δ: “Elution rate is 1.0% or more and less than 3.0%. Practical use is possible.”
×: “Elution rate is 3.0% or more. There is a problem in practical use.”

(Battery characteristics evaluation)
The charge / discharge cycle test of the lithium secondary battery electrode evaluation cell produced above was performed. The discharge capacity at the first time was taken as 100%, and the discharge capacity after 100 hours at 60 ° C. was measured to obtain the rate of change (the closer to 100%, the better). The evaluation results are shown in Table 2.
A: “Change rate is 99% or more. Particularly excellent.”
○: “Change rate is 95% or more and less than 99%. No problem at all”
○: “Change rate is 90% or more and less than 95%. No practical problem”
Δ: “Change rate is 80% or more and less than 90%.
X: “Change rate is less than 80%.

  As shown in Table 2, when the composition for a secondary battery electrode including the resin fine particle dispersion produced in Production Example 1-15 is used, the balance between the electrolytic solution resistance and the adhesiveness can be obtained. The decrease in discharge capacity is suppressed even after 60 hours at 60 ° C. On the other hand, when the composition for a secondary battery electrode containing the resin fine particle dispersion and PVDF produced in Production Example 16-18 is used, a decrease in electrolytic solution resistance, adhesion, and battery characteristics is observed.

Claims (8)

Production of a resin composition for polymerizing a mixture containing a radically polymerizable ethylenically unsaturated monomer (A) and a polyamide resin (B) in an aqueous medium containing a surfactant, a polymerization initiator, and water as essential components a method, a non-aqueous, characterized in that the polymerization of average particle diameter of the (a) and the mixture was forced emulsification in the presence of a surfactant and water emulsion of (B) after the 2μm or less The manufacturing method of the binder resin composition for secondary battery electrodes. The radically polymerizable ethylenically unsaturated monomer (A) is a carboxyl group-containing ethylenically unsaturated monomer (f), a sulfonic acid group-containing ethylenically unsaturated monomer (g), or a phosphate group-containing ethylene. Unsaturated monomer (h), epoxy group-containing ethylenically unsaturated monomer (i), amide group-containing ethylenically unsaturated monomer (j), amino group-containing ethylenically unsaturated monomer (k) ) And a hydroxyl group-containing ethylenically unsaturated monomer (l) at least one monomer selected from the group consisting of the monomers selected from the group, and the total of all ethylenically unsaturated monomers method for producing a nonaqueous secondary battery electrode binder resin composition according to claim 1, characterized in that it comprises 0.1 to 50 wt% in 100 wt%. The radically polymerizable ethylenically unsaturated monomer (A) is an alkoxysilyl group-containing ethylenically unsaturated monomer (c), an N-methylol group-containing ethylenically unsaturated monomer (d), and one molecule. At least one monomer selected from the group consisting of monomers (e) having two or more ethylenically unsaturated groups in the total of monomers selected from the group, The method for producing a binder resin composition for a non-aqueous secondary battery electrode according to claim 1, wherein 0.1 to 5% by weight is contained in 100% by weight of the total mass. The non-water according to any one of claims 1 to 3, wherein the radically polymerizable ethylenically unsaturated monomer (A) comprises the carboxyl group-containing ethylenically unsaturated monomer (f) as an essential component. The manufacturing method of the binder resin composition for secondary battery electrodes. The method for producing a binder resin composition for a nonaqueous secondary battery electrode according to any one of claims 1 to 4, wherein the polyamide resin (B) is a dimer acid-derived polyamide resin. Method for producing a nonaqueous secondary battery electrodes are use a non-aqueous secondary battery electrode binder resin composition obtained by the process according to any one of claims 1 to 5. Method for producing a nonaqueous secondary battery are use a non-aqueous secondary cell electrode obtained by the process of claim 6 wherein. The manufacturing method according to claim 7, wherein the non-aqueous secondary battery is a lithium ion secondary battery.